Antone,
Yes we are still here. It has been much more civilised down here than up in the Lab Classic with flame wars going on. Yikes.
It sounds like using Odd box configurations is best for Horizontal sub arrays? Which isn't an ideal amount of boxes for a Horn sub. I'm also thinking that LAB's and BT7's (in pairs to make on large horn mouth) will start Beaming at around 75Hz
Well yes and no. As you will have seen from Don Keeles' paper the maths for a Bessel function gives you odd numbers of units. BUT. The individual elements/units can be made up of a number of boxes. Ivan pointed out that you make arrays of arrays. Remember that using the Bessel principle is to try to achieve an array that radiates like a single unit. The spaced line concept is used to achieve dispersion like a horizontal line array. The audience at the front only get to be close to a couple of sub boxes. Unlike stacking the boxes either side of the stage. Where people standing to the side hear far too much bass and the people in the middle can often have either not enough or suffer power ally depending on where they stand. Two different concepts. It all depends on what you are trying to achieve.
Both the single block and the line achieve roughly the same spl in the far field. In the nearfield the line has less spl because not all the boxes combine constructively. Same deal as a vertical line array operating at higher frequencies. Same principles apply, just the wavelength is different.
It will be interesting for you to try some real experiments. Not that many people have tried.
Iain.
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Topic: Horizontal Subwoofer Line Arrays (Read 9769 times)